Vito, Thorn of the Dusk Rose

Whenever you gain life, target opponent loses that much life.
{3}{B}{B}: Creatures you control gain lifelink until end of turn.

Heliod's Intervention

Choose one —
• Destroy X target artifacts and/or enchantments.
• Target player gains twice X life.

Sanguine Bond

Whenever you gain life, target opponent loses that much life.

False Cure

Until end of turn, whenever a player gains life, that player loses 2 life for each 1 life they gained.

Plague Drone

Flying
Rot Fly — If an opponent would gain life, that player loses that much life instead.

Defiant Bloodlord

Flying
Whenever you gain life, target opponent loses that much life.

Carnival of Souls

Whenever a creature enters, you lose 1 life and add {B}.

Tainted Remedy

If an opponent would gain life, that player loses that much life instead.

Kenrith, the Returned King

{R}: All creatures gain trample and haste until end of turn.
{1}{G}: Put a +1/+1 counter on target creature.
{2}{W}: Target player gains 5 life.
{3}{U}: Target player draws a card.
{4}{B}: Put target creature card from a graveyard onto the battlefield under its owner's control.